Structure-based viscosity model development for titania aluminosilicate slags

Abstract

ABSTRACTBased on the structure of melts, a model has been developed that estimates the viscosity of the fully liquid melts in the CaO–MgO–Al2O3–SiO2–TiO2 systems. Three kinds of tetrahedral ([SiO4]4−, [AlO4]5−, and [TiO4]4−) are considered in the titania aluminosilicate slag. According to the hole theory of melts, this model provides a link between the viscosity and the structures of the melts. The present model is capable of predicting the viscosities in the CaO–MgO-–Al2O3–SiO2–TiO2 systems with wide composition and temperature ranges above liquidus; the average of relative errors for this model was approximately 20.0%. From the model calculation results, the addition of TiO2 decrease the viscosity of slag under non-reducing atmosphere. The ability of increasing viscosity follows the order: SiO2> Al2O3> TiO2> CaO. Due to the charge compensation and unit size effect, the replacement of TiO2 by Al2O3 will result in the increase of viscosity.